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  Assistive Communication Device Technology: Ethics and Possibilities in Therapy with Non-Speaking Clients

  Amanda Bursch

  Music therapy is a healthcare field wherein music experiences and the myriad relationships formed between client(s), board-certified music therapist(s), and music activates health-oriented changes (Bruscia, 2014). Within this field there are multiple facets that directly impact the client’s experiences; these include: arrangement of the therapy environment, role and function of music experiences, therapeutic relationships, and communication in verbal and non-verbal forms. However, there is a gap in the education and training of music therapists concerning alternatives to verbal communication, and the use of these alternatives in therapy. Through interviews and analysis, this thesis presents findings regarding the experiences of one non-speaking music therapy participant, and three board certified music therapists with relevant expertise, to empower current and student music therapists to advance their engagement with non-speaking clients in music therapy.

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  Baby Showers in Hindu and Bulgarian Cultures: Food and Festivities

  Casey Tirado and Jayilin Barksdale

  Part of a course project on intercultural communication, which can be expressed and studied in myriad ways. The students of CMM 316.01 investigated various forms of cultural expression by comparing and contrasting the ways a particular form is used by multiple cultural groups. Specifically, each group researched and presented about the ways food, music, festivals, rituals, dance, clothing, and other artifacts communicate cultural identity in at least two different cultures.

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  Beaver Activity and Tree Preference at Glen Helen Nature Reserve

  Dustin Holmes

  Ecosystem engineers are vital for natural areas, having a large impact on species richness and ecosystem health. An example is the North American beaver (Castor canadensis). Beavers can radically alter their environment through the construction of dams, which creates new aquatic habitats, leads to greater water availability, and increases nutrient availability for plants and animals. Around two years ago a beaver family began to build a dam in Glen Helen Nature Reserve (Yellow Springs, OH), and since then have completed construction of a dam and a lodge. This has caused significant flooding of the stream that the dam was built on and an opening of the canopy due to the beavers removing many large trees within the area. Our aim was to study the effects that this new beaver colony has had on trees in the area and how the beavers are affected by the local fauna and human activity.For this objective, we set up three remote trail cameras to capture beaver presence and activity. Cameras were active for a month, from Nov 15 to Dec 15, 2022. We also monitored and documented the location of trees that showed any signs of beaver activity so that we could identify what tree species were preferred by the beavers. We collected the cameras and reviewed what was captured, following up with analysis of the data collected. We documented 141 photos and videos of beavers during our study. They were primarily active at dawn, and seemed to avoid other mammals and humans. It was also determined that the beavers mainly preferred medium sized sycamore (Platanus occidentalis) and hackberry trees (Celtis occidentalis) over other slower growing tree species. This data will aid in the management of Glen Helen Nature Reserve and provide insight on what attracts beavers to locations for their dam.

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  Be There, Will Be Wild!: An Analysis of the Participation of Violent Militant Extremist Groups in the January 6 Attack on the Capitol Building

  Jacqueline Eckhart, Sarah Collins, Emma Blair

  In this presentation, we offer an analysis of the participation of violent extremist militia groups in the January 6, 2021 attack on the U.S. Capitol building. Understanding the activities of violent extremist militia groups is a critical need in today's society. In an October 2022 report, the Department of Homeland Security and FBI identified "domestic violent extremists" as "one of the most persistent threats to the United States today." Using tools for the analysis of propaganda, we examine not only the groups themselves, their role in the attack, and the ideologies motivating their actions, but also the societal context surrounding the event and the role that media played. The participation of these groups in the attack is examined as part of a larger system of propaganda, through which institution(s) acting as the source of propagandistic messages, with the assistance of other agents, utilize media to manipulate the cognitions, shape the perceptions, and direct the behavior of a target audience to advance their own partisan interests, regardless of whether their actions promote the common good.

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  Bottom-up Approach to Rebuild Synergy in Biofilms to Stimulate the Degradation of Recalcitrant Polymer Coatings

  Anna Blumberg

  The movement toward more environmentally friendly approaches to thwarting biofilm formation on marine and aerospace equipment has led to a more comprehensive approach to deconstructing and identifying the complex interactions with biofilms on polymer coated surfaces. We will present results from the biodegradation of defined thermoplastic polyester polyurethane and polyether polyurethane coatings using single environmental strains of Bacillus megaterium, Papiliotrema laurentii, and defined mixtures of these two organisms as both liquid cultures and as biofilms on polymer coated surfaces. We will show the changes in population dynamics using a quantitative PCR approach and selective agar plate based assays using antifungal or antimicrobial agents. We will present how under nutrient limited conditions these two organisms appear to control their activity and population density to survive on the carbon sources released from the successful hydrolysis of the synthetic coating. These data show how a prokaryote and eukaryote originally isolated from the same environmental consortium inside of an aircraft interact to affect the degradation of a coated surface over time.

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  Branched Chain Amino Acids in the Regulation of Listeria monocytogenes Toxin Production

  Luke Camden

  Listeria monocytogenes is a human pathogen with many virulence genes that contribute to infections. The expression of these genes is highly coordinated in response to different environmental signals. For example, the transcription factor CodY plays an important regulatory role in virulence gene expression in response to branched chain amino acids (BCAAs), including leucine, isoleucine, and valine. In addition to BCAAs, propionate is also a key environmental signal that can influence L. monocytogenes virulence gene expression. In fact, anaerobic exposure to propionate resulted in an increase in the production of the toxin listeriolysin O (LLO). We hypothesized that CodY was involved in mediating the upregulation of LLO production in response to anaerobic propionate exposure. To test this hypothesis, hemolytic assays were performed to measure and compare LLO activities in wildtype L. monocytogenes and a CodY-deficient mutant (ΔcodY) grown under various conditions. After testing different media types and using different data analysis methods, our results showed that CodY was not required for the upregulation of LLO production by anaerobic propionate exposure. However, CodY may be involved in the upregulation of LLO production by anaerobic exposure to propionate and isoleucine. In conclusion, the role of CodY in L. monocytogenes response to propionate might be more complicated than anticipated. There are likely other mechanisms that are involved in association with the CodY/BCAA regulatory pathway in mediating the regulation of virulence genes in L. monocytogenes.

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  Bring Back Manly Men: An Examination of How Extreme Male Gender Stereotypes Are Portrayed in the Media

  Alayna Yates

  In the December 2020 issue of Vogue US, Harry Styles was the first male cover model in the famous fashion magazines' long history, and he defied traditional male gender fashion norms by wearing a lacy, baby blue dress. Conservatives took to Twitter in outrage with Styles' breaking of traditional gender norms. Members of the LGBTQ+ community asked why an affluent, heterosexual, white, cisgender man had suddenly become the poster child for something drag queens and cross-dressers have been doing for decades. The argument quickly gained two sides, both in disapproval for the pivotal cover photo. Beyond this specific case, it's important to go back in history and examine what does a "manly man" look like? What do they act like? And why? What teaches and reinforces such toxic masculinity? Compared to violent movies and video games, fashion magazines are a vastly different medium that opens up the discussion of what men's fashion looks like today and how times are changing. Playful engagement with clothes and textiles has opened up the arena in which Styles was able to operate for the Vogue US cover shoot, but is this his story to tell? Should a cisgender, heterosexual man be the example when members of the LGBTQ+ community have similarly experimented with fashion? The portrayal of gender stereotypes in the media is complex and makes for an important discussion about how these stereotypes may evolve or change throughout time.

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  Bringing New Methods and Model Organisms into the Pursuit of the Genetic, Developmental, and Evolutionary Basis of a Morphological Trait

  Jada Brown, Logan Brubaker, Allison Pavlus, Victoria Fowler

  The development of animal form is directed by the operation of Gene Regulatory Networks (GRNs) that utilize transcription factor genes to control the spatial, temporal, and even sex-specific patterns of trait-building realizator genes. These patterns of gene expression result from the encoded GRN transcription factor proteins interacting with binding sites in the cis-regulatory elements (CREs) of their directly-regulated target genes. Since many transcription factors and realizator genes are older than the traits they govern, trait evolution arises from genetic changes that altered the uses of these more ancient genes. A major goal for the field of evolutionary-developmental (or evo-devo) biology is to understand how traits originate, diversify, and become lost by changes to key regulatory genes and their connections made with CREs for the ultimate realizator genes of GRNs. We are investigating the evolution of a GRN for a rapidly evolving fruit fly pigmentation trait present in an experimentally convenient model species, and we propose to bring genetic investigations into closely-related emerging model species. Our studies will focus on how the male-specific pattern of abdominal pigmentation emerged in the fruit fly lineage of D. melanogaster and how this trait was modified and lost in related species. In order to reach our goals, experiments and methods will have to confront several challenges. These include identifying the critical CREs with massive genomes, reconciling how gene expression patterns can evolve when regulated by multiple redundant CREs, characterizing gene function in multiple species, and testing the necessity and sufficiency for cases of gene function and CRE evolution in species possessing the ancestral, derived, modified, and lost pigmentation trait. While these goals seem daunting, success will undoubtably push the field of evo-devo much closer to one of its most ambitious goals.

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  Buggin' Out about Solar Prairies

  Raef Khamis Ali Saif Al Hamedi, Grace Litavsky, Abbey Raison, Sarah Metz, Rianna Soltis

  The City of Dayton is interested in implementing two new solar fields similar to University of Dayton’s established solar prairie at Curran Place. The proposed sites were both managed lawns, one of which was in the city’s water treatment plant (referred to as Water Treatment) and the other is a brown field where a paint factory burned down in 1987 (referred to as Sherwin Williams). Insects are an important part of ecosystems because they are important to food webs and aid in pollination of plants. The question we wanted to answer was if the established solar prairie at Curran Place is a beneficial ecosystem that supports high insect biodiversity and if the proposed sites should be treated in the same way. Our hypothesis was that the solar prairie would be more biodiverse than the managed lawns/proposed solar sites. We set up four transects at each city managed lawn and six transects at Curran place (four under the solar panels and two in the prairie vegetation surrounding panels), and at each transect we placed pitfall traps, pan traps, and sweepnetted along the transect. After sorting the captured insects by order in the lab, we found that the established solar prairie at Curran Place had the lowest total number of insects, but the highest insect biodiversity out of all three sites. This study shows that the diversity of flowering plants is beneficial for insect populations as it promotes biodiversity. If the City of Dayton moves forward with implementing solar prairies on these lawns, planting a similar seed mix and applying similar treatments to these two sites as the Curran Place would create a diverse ecosystem for native insect populations.

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  Calling Out, Calling In, Calling On: A Model for Challenging Injustice

  Emma Sawchuk, Nicholas Bridgett, Jarrett Dixon

  Dr. Loretta Ross of Smith College developed a course on "Calling In" as an alternative to calling people out for their roles in perpetuating injustice, and she argues that it is to the human rights movement was nonviolence was to the civil rights movement. This poster will explain what she means by "calling in" and "calling on" and will explain the significance of these approaches for UD's culture.

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  Capital Embodiment: White Beauty and Bodies in Sally Rooney’s Debut Novel

  Josie Forsthoff

  Beauty standards that have long been understood by feminist theorists as sexist also have a history of being rooted in racism. By reproducing the white, slender representations of beauty uncritically, authors potentially perpetuate the racist, classist, and sexist hierarchies in which our cultural norms are rooted. Popular, contemporary author Sally Rooney consciously writes about the privileges of wealth but fails to write in the same way about the capital of beauty and slender bodies. My literary analysis focuses on the political power and implications of the white beauty and embodiment of Frances in her debut novel from 2017. Rooney’s representation of white women is detrimental, I argue, only insofar as the power of whiteness and thinness that is written into their bodies is unclaimed and uncriticized. The thin beauty ideals which oppress and empower women within what bell hooks calls ‘capitalist white supremacist patriarchy’ make embodiment political especially for women at the top like Rooney and her characters. Frances experiences white beauty and embodiment as inhumane perfection and punishment that prevents connection despite exciting desire.

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  Career Prediction via Historical Information

  Abhijeet Gupta, Shruti Ajay Singh, Aditya Shrivastava

  The career dataset introduces the question of how we can predict an individual’s career path in the future. And this can have a variety of application in the industry including enhancing human resources, career guidance, keeping track of future trends, et al. In this paper we propose a method to predict an individual’s career collected using LinkedIn, into two class labels named, Position and Domain. Here, Position has 8 labels defining the position names and Domain has 6 labels defining the industry domain. To predict our findings, the career dataset is tested on six different multiclass multiouput classifiers, and among those the best classifier is finalized for our dataset that predicts out defined class labels upto an accuracy score of 90% approximately.

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  Cell-Membrane Hydrophobicity of L. monocytogenes is Modulated by Propionate and Oxygen Levels

  Angela Murrin, Matthew Austin

  Bacterial hydrophobicity is a key envelope property relevant to pathogenesis and adhesion to surfaces in various food processing and healthcare settings. How hydrophobicity is modulated by environmental conditions is often unclear. In this project, we investigated how two relevant environmental signals, propionate and oxygen, influence bacterial hydrophobicity. Our model organism is Listeria monocytogenes, a Gram-positive foodborne pathogen capable of causing infections with high mortality rates. Despite stringent sanitation procedures, L. monocytogenes persists in the food processing environment and often causes costly food recalls as well as outbreaks. It is unclear whether the cell-surface hydrophobicity of L. monocytogenes contributes to the persistence and how the hydrophobicity may be modulated by environmental signals. Therefore, using various non-polar, organic reagents and a modified procedure from Salas-Tovar et al., the cell-surface hydrophobicity of L. monocytogenes strain 10403s under both aerobic and anaerobic conditions was analyzed. Preliminary results suggest that the types of non-polar reagents used in the study can influence the hydrophobicity estimates. Furthermore, bacteria grown in aerobic conditions exhibited a higher level of hydrophobicity than those grown in anaerobic conditions. Bacterial cultures grown in the presence of a 25 mM concentration of propionate also exhibited a higher level of hydrophobicity than those grown without propionate. These results suggest that hydrophobicity of L. monocytogenes can be modulated by oxygen levels as well as propionate.

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  Centuries of Oppression: A Comprehensive Advocacy Campaign for the Hazara Genocide in Afganisthan

  Darla Hastings, Claire Kelly, Illiana Jones, Matthew Ostermueller, Jillian Tore, Emily McNamara, Katherine Bardine, Ashya Moore, Estela Casas, Lydia Artz

  Based on collaborative work with the World Hazara Council (WHC), this panel presents the work of the International Studies (INS) Senior Capstone project. The project focused on the centuries of persecution and genocide faced by the Hazaras, an ethnic group in north-central Afghanistan. As a class, we advocated for the recognition and increased awareness about the persecution and genocide against the Hazaras. The Hazaras practice Shi’a Islam and are recognizable through their Asiatic appearance. Considering that Afghanistan is a predominantly Sunni country and dominated by the Pashtun ethnic group, Hazaras have faced ongoing discrimination. The recent withdrawal of the United States from Afghanistan, which enabled the Taliban takeover of Kabul in 2021, has further compounded the atrocities faced by the Hazaras For instance, the Kaaj Education Center in Kabul was bombed on September 30th, 2022. This resulted in the death of 58 students, most of whom were young Hazara girls, and injured 110 others. By means of intentional conversations, our advocacy work included: the United Nations to recognize the crimes against the Hazaras as a genocide; raising scholarship funds for Hazara women; organizing petition signings and letter writing campaigns; disseminating information through social media, and lobbying government officials to increase visas for the Hazaras. This work has enabled us to closely engage with structural obstacles faced by marginalized communities, intersectional approaches to advocacy work, and understanding patterns of discrimination. Considering the limitations of the semester, as INS students we brought the situation of the Hazaras to light in various forms. Together we hope this work can continue beyond us and in other such areas of the globe.

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  Characteristics That Impact Use of Force in Suspect and Officer Interactions

  Hope Walsh, Nathan Haitz

  With the rise of Black Lives Matter and the urge for police reform, policing in society has become possibly the most controversial issue in modern American politics. While efforts have been made to reform, the varying sociological issues regarding this issue and its outcomes have not yet been fully understood. Given these circumstances, measuring and analyzing police-citizen interactions and outcomes are vital tools in discovering possible solutions to this issue. The study presented uses information on police-citizen interactions in Phoenix, Arizona and includes key factors that may result in a more or less aggressive response from police officers. The information used in this study from this dataset specifically analyzes the prominence of location in police-citizen interactions with other contributing factors. Prior research has concluded that the people most affected by police use of force are typically minorities, specifically black individuals. However, using the Phoenix Use of Force dataset, police response in this instance was measured against an ordinal outcome through a correlational study. Although the main factor being measured emphasized location, other factors such as age, race, sex, influence, criminal activity, hazards, weapons, and injuries were included as secondary factors. Certain variables within the dataset were re-coded to present themselves as dichotomous or to simplify their meaning into a more ordered structure. These secondary variables were integrated with the primary independent variable forming a regression model for further analysis.

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  Characterization of an Exact Electron Correlation Symmetry in AHCs Using MO Theory at the Single CI Level of Approximation

  Christina Farwick

  Electron-electron repulsion in a quantum system facilitates the correlated motion of electrons, or electron correlation. The extent to which the movement of an electron is influenced by surrounding electrons is proportional to the correlation energy. This project explores unique electron correlation characteristics manifested in the excited singlet states of alternant hydrocarbons (AHCs) – specifically, butadiene and hexatriene. Data was generated using the semiempirical Pariser-Parr-Pople Method, which combines molecular orbital (MO) theory approximation techniques and configuration interaction (CI) calculations. Slater determinants are used to derive configurational wavefunctions that account for all possible single-electron excitations. Each electronic state �� can then be expressed as a linear combination of the singly-excited configurations, with coefficients and corresponding transition energies calculated using the CI method. The results indicate that certain wavefunctions – referred to as plus and minus states – are solely comprised of paired configurations (in equal magnitude), and all other coefficients are zero. The identical wavefunctions of the paired configurations allow for exact electron correlation symmetries to be demonstrated, yielding uncorrelated plus states (��+ > 0 → alternancy heap) and correlated minus states (��– = 0 → alternancy hole). Analysis of each electronic state transition energy as a function of the range of electron-electron repulsion shows that at short ranges, the plus state energy increases due to the presence of alternancy heaps, while the minus state decreases because of alternancy holes. These results are consistent with the exact symmetries derived for the excited singlet states of AHCs.

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  Charging an capacitor using a transducer and sending data to cloud

  Hanok Dan Bunga

  To convert the mechanical energy to electrical energy using piezo electric effect and storing the current produced in a capacitor and sending data from capacitor to cloud using electric sensor and microcontroller is the basic concept and this current when stored in larger scale is used for charging electronic devices. Hence we collect the amount of current produced using this phenomenon and we can use this current when it met required limit.

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  Chess Across Global Cultures

  Ruth Eckhart and Christian Gordon

  Part of a course project on intercultural communication, which can be expressed and studied in myriad ways. The students of CMM 316.01 investigated various forms of cultural expression by comparing and contrasting the ways a particular form is used by multiple cultural groups. Specifically, each group researched and presented about the ways food, music, festivals, rituals, dance, clothing, and other artifacts communicate cultural identity in at least two different cultures.

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  Civil Resistance Works

  Kyra Hughes, Garrett Kemper, Sierra Rummel

  UD alum Erica Chenoweth, now Frank Stanton Professor of the First Amendment at Harvard Kennedy School and a Susan S. and Kenneth L. Wallach Professor at the Radcliffe Institute for Advanced Studies at Harvard University, has collected data demonstrating that movements of nonviolent civil resistance are effective. This poster will explain her findings and illustrate her points with reference to the Women of Liberia Mass Action for Peace movement led by Leymah Gbowee.

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  College of Arts and Sciences Dean's Showcase: The Fitz Center for Leadership in Community

  Abigail Shahady, Alexis Taylor, Destiny O'Neal, Madeline McEldowney, Kathryn Riddle, Grace Hungerford, Nicholas Beltran, James Lambert, Abishek Eagala

  The Fitz Center for Leadership in Community addresses community identified challenges by cultivating reciprocal, collaborative, and inclusive partnerships and learning environments to catalyze a more healthy, just, and equitable future for the Dayton region. The Fitz Center will be presenting its five student programs through Pecha Kucha presentations. As the the audience learns about the Health Equity Fellows, Educational Equity Programs, Dayton Civic Scholars, Ethics and Leadership, and the River Stewards, they will also see how our students learn to be reciprocal and responsive partners, partner with communities to move forward shared goals, and become leaders in ways that shape their future vocations and continue their impact.

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  Collision Prevention System using Ultrasonic Sensor, Arduino, and Node-RED

  Rahul Bhattar

  The main aim of this project is to solve the accidents or collisions if an object is close to the sensor. the basic setup would be using an ultrasonic sensor with an Arduino board and node-red. Usually, the setup would include by connecting an ultrasonic sensor to an Arduino board, programming the board to read the sensors data and creating the node-red flows to display an alert message when the object is too close. This project can be useful in a variety of applications like home automation and Robotics.Also, maybe I can try to enhance depending on the temperature if the window is open or not.

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  Communication Optimization in Tiny Federated Learning

  Rahul Theresaraj

  Tiny Federated Learning is a combination of Tiny Machine Learning (TinyML) and the Federated Learning (FL) approach. TinyML is a field of study that involves machine learning and embedded systems that can be run on small, low-powered devices, and Federated learning is an emerging approach used to train a decentralized machine learning model across multiple edge devices. Tiny Federated Learning is a federated learning approach on tiny edge devices with low latency, low power, and low computational cost. This approach is helpful in many ways. The edge device can learn new things every day and updates itself to do the tasks better.TFL trains a shared Machine learning model in Embedded devices like microcontrollers while keeping the training data locally without sharing it with the Server. TFL suffers from the problem of transmitting the data from the edge devices to the server as edge devices have limited computational power.To solve this problem, we design an approach for reducing the transmission cost between edge devices and the server. More specifically, we build a model by pruning approach to reduce the model computational cost and find effective means of communication of data from the trained data to the Server. We focus on sending only the instance of newly learned model update to the server rather than sending the whole model update to the server. The Proposed approach reduces the uplink transmission cost. Our Overall objective is to build a model that can perform better and learn better on an embedded device and also sends updates to the server by reducing computational and transmission cost.

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  Competition Versus Choice: Evolution Along a Narrow Path in Drosophila β2 Tubulin

  Olivia Parson

  The Drosophila melanogaster β2 protein (Dmβ2) has sustained a long evolutionary stasis for the last 60 million years. Even small changes to the protein’s primary amino acid sequence render it non-functional, suggesting its stasis may be due to stringency in the structure/function relationship. This project seeks to understand what has prevented Dmβ2 from evolving, with the two main hypotheses being that Dmβ2 either exists as an ideal protein configuration that competitively bests all alternates or that Dmβ2 is the only possible configuration that will support spermatogenesis in Drosophila melanogaster. In order to test these hypotheses, the ability of other proteins to rescue β2 function must be assessed. Previous work done to test β2 function used the major, non sperm-generator tubulin (β1) as a backbone to test the function of candidate sperm-generating residues. While sperm-generating residues were identified, none were sufficient to rescue fertility in a Dmβ2 null background. This project represents a different approach to analyzing the evolutionary stasis of Dmβ2 by testing the ability of a known sperm-generating ortholog from Glossina morsitans (commonly known as the tsetse fly) to rescue fertility. This sequence is 96% identical to Dmβ2 and is of particular interest because it is the closest relative to Drosophila melanogaster that possesses a variation in β2 sequence. When expressed in a Dmβ2 null background, the tsetse fly β2 (Gmβ2) generates long-tailed, fertile sperm when examined by light microscopy on testis samples and fertility tests between transgenic males and virgin wild-type females. This evidence supports the first of the two hypotheses outlined above, that β2 alternates exist but Dmβ2 is competitively superior. This shows the potential for β2 to participate in the process of evolution, potentially through allelic effects on sperm-tail length, which plays an important role in the retention of sperm in the female reproductive tract. Comparative analyses of outgroups, such as the human β2 ortholog (Hsβ3), will provide further information necessary to assess the roles of generic aspects of β2 such as motility versus more lineage-specific properties such as sperm tail length in the process of spermatogenesis.

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  Connecting Compositions of Gustav Holst: Folk Songs and The Planets

  Rachel Dalrymple

  Gustav Holst, a British composer from the early 1900’s, is most well-known for writing “The Planets,” an orchestral suite with movements for each of the planets and their corresponding astrological personalities. A significant portion of Holst’s lesser-known compositions were based on British folk songs. In my thesis, I am exploring the connections between Holst’s folk song-based pieces and “The Planets” in terms of the compositional devices of meter, tonality, orchestration, and melody. These compositional devices are threads that connect both types of pieces together and define Holst’s characteristic style.

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  Conservation of testis protein structure and function revealed in a swapping experiment of human testis tubulin in the fly D. melanogaster

  Rihanna Domingos

  Drosophilid spermtails are the peacock feathers of the world of sperm by virtue of their incredible length, from 2mm in Drosophila melanogaster to over 5cm in D. bifurca. D. melanogaster use a specialized, testis-specific B2 tubulin isoform to generate the microtubule scaffolding of their spermtail axoneme. Structure/function tests show B2 does not tolerate change, even small alterations in its amino acid sequence render it non-functional. This sensitivity is reflected in its evolutionary stasis, the Drosophilid B2 protein has not evolved at a single amino acid in 60 million years. There are two hypotheses for its stasis, either 1) the DmB2 protein is an ideal configuration that has outcompeted variants over the past 60 million years, or 2) it is the only configuration able to support the Drosophilid sperm by evolving into a corner it cannot evolve out of that is resistant to evolutionary change and templates long axonemes. This is tested by assessing the ability of the Homo sapiens sperm-generating beta tubulin protein HsB3 to replace Drosophila B2 in transgenic Drosophila flies. HsB3 is capable of generating sperm, despite being only 90% identical to Drosophila B2. Conversely, a chimeric B1-B2 tubulin over 97% identical to Drosophila B2 cannot. Comparing the 3D protein structures reveals testis tubulins have conserved protein domains and function, indicating convergence on testis-supporting isoforms across deep evolutionary time.